Bicycle frame



FIG. 1 is a front perspective view of a bicycle frame showing my new design;

FIG. 2 is a rear perspective view thereof;

FIG. 3 is a right side elevation view thereof;

FIG. 4 is a front elevation view thereof;

FIG. 5 is a rear elevation view thereof; and,

FIG. 6 is a top plan view thereof.

The broken lines showing various parts of a bicycle are provided for the purpose of illustrating environmental structure and do not form part of the claimed design. 

CLAIM The ornamental design for a bicycle frame, as shown and described. 